Means for positioning cable under tension



Sept. 18, 1962 R. D. CARR 3,054,596

MEANS FOR PosITxoNING CABLE UNDERTENSION Filed Maron 19, 195s x I N VEN TOR.

ATTCI R N EYE United States Patent Office 3,054,596 Patented Sept. 18, 1962 3,054,596 MEANS FOR POSITIUNING CABLE UNDER TENSION Robert D. Carr, R0. Box 53, Victoria, Tex. Filed Mar. 19, 1958, Ser. No. 722,589 1 Claim. (Cl. 254-51) The present invention relates to a method of and means Ifor positioning cable, wire or strands under tension for use in the fabrication or formation of concrete products.

A fundamental object of the present invention is to provide a means whereby strands or cables can be moved from one position to another position so that with the strands embedded in concrete members, the completed concrete members will have increased rigidity or strength.

Another fundamental object of the present invention is to provide a means whereby -reinforcing strands can be moved from a straight formation to a formation in which the end portions of the strands are inclined, and wherein the intermediate portions of the ystrands are straight, the present invention utilizing a double acting ram whereby .the strands can be moved to a position so that they can be anchored in place by a hold-down mechanism.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and' combinations pointed out in the appended claim.

The invention consists in the novel parts, construction, arrangements, combinations and improvements herein shown and described.

The accompanying drawings, referred to herein and constituting a part hereof, illustrate one embodiment of the invention, and together with the description, serve `to explain the principles of the invention.

Of the drawings:

FIGURE 1 is an elevational view illustrating the double acting ram for use with the present invention.

FIGURE 2 is an elevational View, with parts broken away and in section, showing the ram in lowered position.

FIGURE 3 is a sectional View taken on the line 3-3 of FIGURE 2.

Referring in detail to the drawings, the numeral 1d indicates the base member or bottom wall of a form which may be supported on a pad such as the pad or support member 11. The present invention is directed to a means for moving `the strands such as the strands 12 from the broken line position shown in FIGURE 2 to the solid line position shown in FIGURE 2 and it will be seen that initially the strands 12 as shown in broken lines, are in a straight formation. However, after the present invention has been carried out, the strands 12 are arranged so that the end portions 2t) of the strands are inclined, while the intermediate portions of lthe strands are straight as indicated by the numeral 21.

For moving the strands from the broken line position shown in FIGURE 2 to the solid line position, there is provided a double acting ram which is indicated generally by the numeral 13, and the ram 13 includes a rod 14 which has its lower end threaded as at 22 for engagement with the base member 10. A collar 15 may be mounted on the lower end of the rod 14. Mounted on the upper end of the rod 14 is a piston or plunger 16 which is arranged within a movable housing or cylinder 17. The numerals 18 and 19 indicate conduits which are connected to opposite ends of the housing 17 whereby hydraulic Huid can be supplied to and from the ram 13.

Secured to the lower end of the housing 17 is a bracket 23 which is provided with spaced apart fingers 24 for engagement with the strands 12.

The numeral 25 indicates in broken lines in FIGURE 2 a hold-down device which is described and shown in detail in my co-pending patent application Serial No. 722,578, now Patent No. 3,013,322 and the hold-down device 25 includes a lower collar 26, and an upper removable sleeve 29, and the collar 26 is provided with a plurality of inclined lugs or fingers 27 which serve to engage the strands 12 when the strands 12 are in their lowered position whereby the Vstrands will be maintained in their proper stressed condition. Each holddown device 25 is yfurther provided with a removable bolt or rod 2S.

From the foregoing, it is apparent that there has been provided a method of and means for deiiecting prestressed .strands for use with pre-stressed concrete. According to the present invention, it will be seen that with the strand 12 initially in the broken line position shown in FIGURE 2, the ram 13 is arranged so that its lower end 22 is anchored in the base 10 of the form. Then, with the fingers 24 of the bracket 23 engaging the Strands 12, it will be seen that by applying hydraulic fluid through the conduit 19, this hydraulic iluid will enter the lower end of the housing 17 so that the ram 13 will move from the position shown in FIGURE l t-o the position shown in FIGURE 2 and this will cause the strand 12 to move from the broken line position shown in FIGURE 2 to the solid line position shown in FIGURE 2 and then the intermediate portion 21 of the strand 12 can be hooked beneath the lugs 27 of :the hold-down device 25 so that the strand 12 will be arranged in such a manner that it will have its end portions 20 inclined at an angle with respect to the longitudinal axis of the concrete member being formed, while the intermediate portion 21 of the strand will have a straight formation. After the strand 12 has been anchored beneath the lugs 27, the ram 13 can be disconnected by unscrewing the portion 22 from the base member 10, so that the ram 13 can be used over and over again. Similarly, as described in my copending application, the sleeve 29 can be removed by unscrewing the bolt 28 so that various parts of the hold-down device 25 can be used over and over again.

Thus, it' will be Seen that according to the present invention there has been provided a method of depressing or deflecting wire, cable or strand under :tension in the manufacturing process being used for the production of pre-stressed concrete products. It is to be understood that the principle of the present invention is not restricted lto any particular product since it can be utilized with any type of concrete unit that is to be put into compression by the use of wire, cable or strand, and the wire, cable or strand is to be placed through the concrete unit under tension in any position other than a straight line.

Primarily the unit -for changing the location of the wire, strand or cable that is under tension, from a straight line is a double acting hydraulic cylinder 13. In actual practice, the ram is adapted to be attached to the casting table or form lit by any suitable method as for example by means of a pin, screw, bolt or the like, and the wire, strand or cable to be pushed down or deflected, is pushed with the housing portion 17 of the hydraulic cylinder by inducing oil under pressure t-o the port or conduit in the end of the cylinder which forces the hydraulic cylinder to a collapsed position as shown in FIGURE 2.

The size of the hydraulic cylinder may be varied as desired depending upon the particular application, and depending on the force required to depress the wire, strand or cable, either individually or in a group, depending upon the requirements. The cylinder 17 has a bracket 23 attached to the lower end of the housing or cylinder which will tit whatever wire, strand or cable pattern that is being used,

After the wire, cable or strand has been deected to 4a predetermined position, it is xed in this position as shown in solid lines in FIGURE 2, with suitable hardware or by means of the hold-down device 2S and then the pressure on the hydraulic cylinder is reversed to the port or conduit 18 in the opposite end so as to lforce the housing 17 to an upward position whereby another strand or group of strands can be aixed to the bracket or 'the housing so that they in turn can be pushed down, unless all are pushed down in the first operation.

Thus, it' will be Seen that there has been provided a novel process for the positioning of cable under tension. In FIGURE 2 the numeral 17 indicates the position of the housing in raised position, while the solid lines indicate the housing in down position. The hold-down device 25 is provided with a removable tapered bushing 29, and the strands 12 are shown in broken lines in FIGURE 2 before depressing, and in solid lines after depressing.

Minor changes in shape, size and rearrangement of details coming within the held of invention claimed may be resorted to in actual practice, if desired.

I claim:

For use with a concrete form of the type that includes a base member, a means for positioning cable under tension wherein the cable is moved from a straight formation to a formation having inclined end portions and an intermediate straight portion, said means comprising a rod having its lower end threaded and adapted to be releasably anchored to .the base member of the concrete form, a collar mounted on the lower portion of the 1 rod above the threaded end thereof, said rod being part of a double acting ram, said rarn including a movable housing, a bracket secured to the lower end of said housing for engagement with the cable being deected, said bracket being provided with spaced apart iingers,

a piston mounted on the upper end of the rod and i said piston being positioned within said housing, said the ram.

ram being hydraulically controlled and actuated, and conduits connected -to opposite ends of the housing whereby hydraulic fluid can be conveyed to and from References Cited in the tile of this patent UNITED STATES PATENTS 

